Police said that Williams was found unconscious around noon in his home in Tiburon, California, near San Francisco.

Williams was best known for his starring roles in classic comedies like “Mrs. Doubtfire,” “Good Morning, Vietnam” and “Jumanji,” but also in acclaimed dramas such as “Dead Poets Society.” He won the Academy Award for Best Supporting Actor for his portrayal of Dr. Sean Maguire in “Good Will Hunting.” He rose to fame while playing Mork the alien in the TV show “Mork & Mindy,” a “Happy Days” spinoff.

In “Dead Poets Society,” Williams plays John Keating, an electric English teacher at an elite all-boys high school. In a quintessential speech, Keating tells his students:

To quote from Whitman, “O me! O life!… of the questions of these recurring; of the endless trains of the faithless… of cities filled with the foolish; what good amid these, O me, O life?” Answer. That you are here – that life exists, and identity; that the powerful play goes on and you may contribute a verse. That the powerful play *goes on* and you may contribute a verse. What will your verse be?

Williams in Dead Poets Society.

Most recently, Williams had starred in the new CBS sitcom “The Crazy Ones.” It was cancelled after just one season. At his time of death, a sequel to “Mrs. Doubtfire” was in the works.

Susan Schneider, the actor’s wife, released the following statement to the New York Times’ Dave Itzkoff:

“This morning, I lost my husband and my best friend, while the world lost one of its most beloved artists and beautiful human beings. I am utterly heartbroken. On behalf of Robin’s family, we are asking for privacy during our time of profound grief. As he is remembered, it is our hope that the focus will not be on Robin’s death but on the countless moments of joy and laughter he gave to millions.”

“It’s not caused by anything, it’s just there,” he said. “It waits. It lays in wait for the time when you think, ‘It’s fine now, I’m OK.’ Then, the next thing you know, it’s not OK. Then you realize, ‘Where am I? I didn’t realize I was in Cleveland.'”

Last month, he spent time at Hazelden Addiction Treatment Center in a continued sobriety program. His publicist told HuffPost at the time that he was doing well.

Though Williams was most celebrated for his acting career, he is also remembered his charitable endeavors. Williams spearheaded Comic Relief, which holds concerts and variety shows to raise money to help the homeless.

In a statement, President Obama said that Williams “was one of a kind… He made us laugh. He made us cry. He gave his immeasurable talent freely and generously to those who needed it most – from our troops stationed abroad to the marginalized on our own streets.”

The actor was also an avid gamer and named his daughter Zelda after the popular video game character. In his last post to Instagram, he paid tribute to his young daughter on her birthday. Zelda Williams is also an actress.

Williams was born in Chicago, Illinois and studied acting at the Juilliard School in New York City.